1. Field of the Invention
The present invention generally relates electrical connectors and, more particularly, to press fit contacts for through-the-hole mounting and a strip of contacts formed of same.
2. Description of the Prior Art
Press fitting of contacts through plated through holes in a printed circuit board (PCB) to provide an electrical connection without solder has been common and basic to the industry since the 1970s. Typically, an electrical contact is provided with a leg or post which is designed to be received within a plated through hole in press or interference fit therewith. This may be achieved by selecting the dimensions of the leg or post somewhat larger than the plated through hole diameter to provide the interference fit by deforming the coating and/or substrate of the plated through hole. Alternatively, the leg or post may be provided along at least one portion thereof with a compliant or flexible region which is compressible when forced into a smaller dimensioned through hole.
Referring to FIG. 1, a press fit contact or terminal 10 in accordance with the prior art is illustrated, following the teachings of U.S. Pat. Nos. 4,156,553; 4,188,715; 4,220,393; and 4,045,868, all issued to Ammon et al. and assigned to Elfab Corporation of Dallas, Tex. Referring to FIG. 1, the prior art terminal 10 is provided with a contact portion 10', a leg or post portion 10" and load bearing shoulders 12, formed between the contact and leg portions, which project laterally in opposite directions as shown. The means for transmitting the force to the load-bearing-, in each instance shoulders is an external tool (not shown) which imparts forces F directly on the terminal's load-bearing-, in each instance shoulders 12, such as an insulator housing with contact cavities containing corresponding load-bearing-, in each instance shoulders by which the forces are transmitted from the shoulders of the housing contact cavity to the corresponding load-bearing-, in each instance shoulders on the electrical terminal 10. The drawbacks of this aforementioned prior art contact include the fact that the load-bearing-, in each instance shoulders 12 formed on the electrical contact or terminal require the contact to include significant projections or protuberances which project laterally of the main body portion of the contact so that the contact becomes wider than would normally be required in a non-press fit design. These load-bearing-, in each instance shoulders 12 also necessarily have sharp corners and edges as a result of the cutting and forming operations in the stamping process. Minimal distances between electrical contacts and sharp corners typically generate undesirable cross-talk in today's high speed electronic systems.